Project Brief

In September 2011, an estimated 2 km of EZ Street Polymer Modified Cold Asphalt Surface was installed for the community of N’dilo (located within the City of Yellowknife).

N’dilo had been waiting for over 40 years for a paved surface for their community, and the EZ Street technology was chosen by the community over other alternatives for its logistical and performance advantages and the long term cost savings that its higher performance would provide over traditional hot mix asphalt surfacing.

The sub-base was prepared the week before surfacing, with the structural integrity and strength of the sub-base being then confirmed by the EZ Street Canada team through standard laboratory and field tests. The confirmation of adequate sub-base strength is conducted for all EZ Street Canada applications prior to installation.

The material had been produced some 2 km away utilizing a standard asphalt plant and stockpiled at the production site for over a week before being installed, allowing for optimal planning and staging, with never any risk of any costly delays. The entire 2 km of surface was installed over 2 full days, and temperatures were as low as minus 4 °C during installation, with no detriment to the project or the material’s performance.

The surface was installed at a depth of 45 mm using standard paving equipment, and compacted with both a standard combination roller and a pneumatic tire roller.

Pavement Testing

Marshall strength/stability tests were performed on the EZ Street material by EBA Engineering with results of 14,600 N being achieved. The standard Marshall results for regular hot mix asphalt installations are expected to be between 16,000 to 18,000 N.

Project Update

In October 2012, (1 year after installation), the test section was revisited to review the conditions of the surface and to see if there was any deterioration.

The surface continues to perform without issue. There are no defects or cracks of any kind on any part of the surface. A similar sized section of traditional hot mix asphalt was installed in another section of Yellowknife close to the same time as this project. The hot mix asphalt section now shows more than 50 full width transverse thermal cracks (all requiring sealing less than 6 months after the section was installed). This amount of immediate thermal cracking is very common to hot mix asphalt installations in the Canadian North.

Main Advantages Illustrated

The EZ Street material was produced and stockpiled in advance of the paving and then installed a number of weeks later with no danger of delays, as the material is stored and installed at ambient temperatures. The material is also impervious to cold or wet conditions, and can be installed with a minimal crew. In this case the same experienced people that produced the EZ Street Asphalt also installed the material allowing the project to take full advantage of their production and installation skills. The EZ Street material was optimally compacted with no heat or time limitations, as opposed to traditional hot mix asphalt, that cannot be properly compacted once it begins to cool.

The complete lack of thermal cracking to date is an unprecedented benefit to the technology, as traditional asphalt installed in Yellowknife invariably develops full-width transverse thermal cracks within its first season.

EZ Street installs with no paver joints or seams as opposed to traditional hot mix asphalt that always comes with this unavoidable inbuilt problem. The seams and joints in traditional hot mix asphalt are weak areas that are likely to be the first point of failure and the beginning of end of the overall surface integrity. EZ Street Asphalt technology eliminates this problem completely. This aspect, combined with its superior strength and stability means a much longer potential life cycle and long-term savings on maintenance and replacement.

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